Pharmacies across the city routinely fail to help non-English speakers understand their prescriptions, raising the chances that customers could harm themselves by taking medicines incorrectly, immigrant advocacy groups charge in a discrimination complaint that they plan to file today with the New York attorney general’s office.

The complaint names 16 pharmacies in Brooklyn, Queens and Long Island, most of them operated by chains. It argues that federal civil rights law and state health regulations require pharmacies to provide linguistic help to guarantee that people who speak little or no English receive equal access to health care. That assistance should include interpreters at pharmacies and written translations of medication instructions, the advocates say.

Nisha Agarwal, a lawyer for one of the groups filing the complaint, said the attorney general’s office had already issued subpoenas to several pharmacies listed in an earlier version of the complaint filed in July. The new version names more pharmacies, and an accompanying report includes more examples of comprehension problems non-English speakers have had.

"The idea is that people should not be placed in danger by not understanding their medication regimen," said Andrew Friedman, an executive director of Make the Road New York, one of the groups filing the complaint, along with New York Lawyers for the Public Interest and the New York Immigration Coalition.

Jeffrey Lerner, a spokesman for the attorney general’s office, said only, "We have an ongoing investigation."

The pharmacies named include six operated by Rite Aid, three CVS stores, three Duane Reade stores, a Walgreens and a Wal-Mart. CVS said it was cooperating with the attorney general. The other companies declined to comment on the pending legal matter, but said they were trying to provide good service for diverse populations.

Tiffani Bruce, a spokeswoman for Walgreens, said the chain provided medication labels in 14 languages and kept a nationwide database of its pharmacists who speak other languages, enabling a pharmacist to call a colleague who can talk to a customer.

CVS said it provided telephone interpreters in 150 languages, and Rite Aid said it tried to hire bilingual pharmacists and provided labels in 12 languages.

In a survey of pharmacists at 200 New York drugstores to be published next month in the Journal of Urban Health, 88 percent said they saw non-English-speaking customers daily, and 80 percent said they had the ability to translate labels, according to Linda Weiss, a senior research associate at the New York Academy of Medicine, who conducted the study. But only 34 percent said they translated labels daily, and 26 percent said they never did.

Many states require hospitals to provide translation and interpretation services in emergency rooms. Last year, New York State’s Department of Health tightened regulations to require that all hospital departments provide interpreters to non-English speakers within 20 minutes.

Health advocates have increasingly used federal civil rights law to push hospitals, nursing homes and clinics to provide language services. Language barriers to health services constitute discrimination based on national origin, they argue, a violation of federal civil rights law, which applies to hospitals because they receive federal funds through Medicare and other programs.

The latest effort aims to expand similar requirements to pharmacies. The complaints also cite the New York Education Law, which requires that medications be labeled in a way that ordinary people can understand. That is meaningless if they are in a language the patient does not comprehend, Mr. Friedman said.

This month, California enacted a law requiring the state’s pharmacy board to implement new requirements for clear prescription labeling by 2011, and to "consider" the needs of non-English speakers.

The advocacy groups provided The New York Times with a copy of the complaint and the accompanying report.

The report chronicles the stories of more than a dozen New Yorkers who said they struggled to understand their prescriptions at local pharmacies. Reyita Rivera, 47, for example, who speaks and reads only Spanish, said she could not understand the printed instructions that came with her antidepressant medication, and ended up taking too much. She said she had to be admitted to a Queens hospital after the medication caused a racing heartbeat.

"That experience scared me a lot. I felt very bad — I thought I was just going crazy," Mrs. Rivera, a Dominican immigrant, said in an interview, speaking through an interpreter.

She said she could not communicate with the staff at her pharmacy in Ridgewood, Queens, and received no printed explanation of the medication in Spanish.

José Cadavid, 63, of Woodside, Queens, said he usually could not get his pharmacists to explain his medication in Spanish. "Whenever I go to the pharmacy I see a lot of people struggling to communicate," said Mr. Cadavid, who immigrated from Colombia. "There’s no one helping them. It affects a lot of people."